<title>Dynamic RAM</title>
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<applet code=Circuit.class archive=circuit.jar width=640 height=600>
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<param name=pause value=20>
<param name=startCircuit value="dram.txt">
<param name=startLabel   value="Dynamic RAM">
<param name=useFrame     value="false">
</applet>
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<p>
This circuit is a very simple model
of <a href="http://en.wikipedia.org/wiki/DRAM">dynamic RAM</a>,
with a capacity of four bits.  There is only one column, with
four rows.
<p>
Select which bit you want with the two inputs labeled "row select".  The output is
on the right.  To write a bit, specify the bit you want to write with the "data" input
and then click the "write" input.  This will charge (or discharge) the appropriate
capacitor.
<p>
The capacitors will slowly drain over time, so each row must be refreshed periodically.
To do this, select the row and click the "refresh" input.


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<br>Generated Tue Dec  7 2010
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